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Hui Tang

Publications and source records attributed to Hui Tang.

17 recordsLinked to original sources
PubMed2006

Genetic polymorphisms of 17 Y-STRs haplotypes in Tibetan ethnic minority group of China.

Haplotypes and allele frequencies for the 17 Y-chromosomal STRs loci, namely DYS456, DYS389I, DYS390, DYS389II, DYS458, DYS19, DYS385a,b, DYS393, DYS391, DYS439, DYS635, DYS392, Y GATA H4, DYS437, DYS438, DYS448 were determined in a population sample of 112 healthy unrelated autochthonous Tibetan ethnic male individuals from Tibet of China. No shared haplotypes were observed. The gene diversity values for the Y-STRs loci ranged from 0.2052(DYS391) to 0.9301(DYS385a,b). The results demonstrate that these loci will be very useful for human identification in forensic cases and paternity tests in Tibetan population of China.

China↗
PubMed2006

Mutations at 17 STR loci in Chinese population.

Knowledge about mutation rates and the mutational process of short-tandem-repeat (STR) or microsatellite loci used in forensic analysis is crucial for the correct interpretation of resulting genetic profiles. We analysed a total of 19,754 samples from 6532 paternity testing cases at 17 STR loci which are commonly applied to forensics. The parenthood in each of these cases was highly validated (probability>99.99%). We identified 178 mutations. Locus-specific mutation rate estimates varied between 7.0 x 10(-5) and 2.2 x 10(-3), and the overall average mutation rate estimate was 8.4 x 10(-4). The observed mutational features for STRs have important consequences for forensic application such as the definition of criterions for exclusion in paternity testing and the interpretation of DNA profiles in identification analysis. In order to enrich the reference data of STRs mutations which are valuable for forensic application, we suggest the establishment of such database and ask the whole forensic community for data contribution including China.

China↗
PubMed2006

An oral tactile interface for blind navigation.

An oral tactile interface was designed and evaluated to provide directional cues through the tactile channel, which may be utilized by a blind traveler to obtain directional guidance in outdoor navigation. The device was implemented as a mouthpiece with a microfabricated electrotactile display on top for tactile presentation onto the roof of the mouth and a tongue touch keypad at the bottom for simultaneous operation by the tongue. An experimental system allowed a user to communicate with a computer tactilely by using the oral interface. Directional cues were presented to the user as line or arrow patterns with four moving directions (leftward, rightward, forward, and backward). Electrotactile presentation on the roof of the mouth was evaluated in experiments of threshold measurement and identification of directional cues. Experimental results from six human subjects showed that the roof of the mouth required stimulation intensities around 15 V for threshold sensation, and around 25-30 V for comfortable and well-perceived stimulation. Furthermore, identification of leftward or rightward movements was highly accurate while performance on forward or backward moving patterns was mixed and varied considerably among subjects.

Adult↗
PubMed2006

[Polymorphisms analysis of mitochondrial DNA in coding area].

OBJECTIVE: To analyze mitochondrial DNA (mtDNA) polymorphisms in coding area and provide a theoretical basis for applying in forensic science. METHODS: The primers of 8162F/8483R and 13070F/13299R were designed according to the Anderson's sequence. Using PCR-sequencing method to detect polymorphisms of mtDNA nt8162-8483 and nt13070-13299. RESULTS: The lengths of the amplicons were 322 bp and 230 bp respectively. There were 24 mitochondrial haplotypes defined by 21 variable positions in both regions. The gene diversity was estimated at 0.751 1, and the probability of two randomly selected individuals having identical mtDNA types was 0.256 4. CONCLUSION: The polymorphic sites within mtDNA coding area can be useful in combination with mtDNA control region in order to increase the discrimination power.

Base Sequence↗
PubMed2006

[Influence of some topical antibiotics and FGF2, EGF and rhGH on the biological characteristics of fibroblasts in vitro].

OBJECTIVE: To investigate the influence of some topically used antibiotics (amikacin, gentamicin, chloromycetin and sulfamylon), basic fibroblast growth factor (FGF2) , epithelial growth factor (EGF) and recombinant human growth hormone (rhGH) on the growth of fibroblasts in vitro. METHODS: Fibroblasts were cultured and passaged. The cultured cells were then divided into control (routine culture of fibroblasts), amikacin (amikacin in respective dose of 0.021, 0.210, 2.100 mg/L), gentamicin (in respective dose of 5, 50, 500 mg/L) , chloromycetin (in respective dose of 0.01, 0.10, 1.00 mg/L), sulfamylon (in respective dose of 5, 10 g/L), FGF2 (2400 U/ml), EGF (2000 U/ml) and rhGH (0.016, 0.160, 1.600 g/L) groups. After the above agents were added to the culture medium respectively, the proliferation of the cultured fibroblasts was determined with MTT method, and the result was expressed as A (absorption) value. The cell cycle was determined with flow cytometry and the morphology of the cells was observed with inverted microscope. RESULTS: (1) MTT method: The A value of fibroblasts cultured with amikacin, gentamicin, chloromycetin and sulfamylon in various doses was obviously lower than that in control group (0.4553 +/- 0.0217, P < 0.05 or 0.01) , and the A value of sulfamylon group was the lowest in two doses (0.1013 +/- 0.0011 for 5 g/L and 0.0950 +/- 0.0041 for 10 g/L, P < 0.01). On the other hand,the A value in FGF2 and rhGH group(0.016 g/L) was much higher than that in the control (P < 0.05). However,theA value in EGF (both doses) and rhGH groups (0.160, 1.600 g/L) was close to that in control (P > 0.05). (2) Cell cycle determination: The proliferation index (PI) of fibroblasts cultured with amikacin in dose of 0.210 mg/L showed no difference compared to that in control (9.63 +/- 0.45)%, (P > 0.05). But the PI of fibroblasts cultured with FGF2, EGF and rhGF in dose of 0.016 g/L was increased significantly (46.76 +/- 2.33)%, (42.30 +/- 1.41)%, and (13.29 +/- 0.47)%, respectively, (P < 0.05 or 0.01). (3) Histological examination of the cells: The number of fibroblasts in elongated or spindle shape was larger, showing a blur contour but high transparency in control as well as in EGF and rhGH groups (both 0.160 and 1.600 g/L doses groups). The number of cells was lower in amikacin, gentamicin, chloromycetin and sulfamylon groups with sharp but irregular contour and lower transparency, and more granule-like materials and vacuoles in the cytoplasm. The cells in the FGF2 and rhGH (in dose of 0.016 g/L) groups exhibited dense with even distribution and slender or spindle shape and with more mitotic figures but blur contour and high transparency. CONCLUSION: Different kinds of the topically used therapeutic agents for burn wounds exert different influence on the biological characteristics of fibroblasts in vitro. The topically used agents for burn wounds should be carefully selected so that wound healing will be promoted and scar formation inhibited.

Anti-Bacterial Agents↗
PubMed2005

System development for multichannel electrotactile stimulation on the lips.

Multichannel pulsatile stimulation is essential for electrotactile presentation of spatiotemporal patterns in sensory substitution through the sense of touch. In this paper, a system for multichannel electrotactile stimulation is presented for studying electrotactile sensation on the lips, a site that has been shown to be highly sensitive but never been assessed for electrotactile applications. The system utilized a demultiplexing scheme to deliver voltage-clamped pulse waveforms to 32 channels corresponding to an array of 4x8 stimulators. Initial testing of electrotactile presentation on the lips was performed in human subject experiments on threshold measurement and two-line separation. For an array of hemispherical stimulators each 700 microm in diameter, the threshold values on the lower lip were averaged at only 8.2 V and intensities for well-perceived stimulation were averaged at around 14.2 V. The testing results suggested that lips were promising sites for electrotactile applications due to their high sensitivity to electrotactile stimulation at extremely low intensities.

Adult↗
PubMed2005

Determination of N-NO bond dissociation energies of N-methyl-N-nitrosobenzenesulfonamides in acetonitrile and application in the mechanism analyses on NO transfer.

The heterolytic and homolytic N-NO bond dissociation energies of seven substituted N-methyl-N-nitrosobenzenesulfonamides (abbreviated as G-MNBS, G = p-OCH(3), p-CH(3), p-H, p-Cl, p-Br, 2,5-2Cl, m-NO(2)) in acetonitrile solution were evaluated for the first time by using titration calorimetry and relative thermodynamic cycles according to Hess' law. The results show that the energetic scales of the heterolytic and homolytic N-NO bond dissociation energies of G-MNBS in acetonitrile solution cover the ranges from 44.3 to 49.5 and from 33.0 to 34.9 kcal/mol for the neutral G-MNBS, respectively, which indicates that N-methyl-N-nitrosobenzenesulfonamides are much easier to release a NO radical (NO(*)) than to release a NO cation (NO(+)). The estimation of the heterolytic and homolytic (N-NO)(-)(*) bond dissociation energies of the seven G-MNBS radical anions in acetonitrile solution gives the energetic ranges of -15.8 to -12.9 and -3.1 to 1.8 kcal/mol for the (N-NO)(-)(*) bond homolysis and heterolysis, respectively, which means that G-MNBS radical anions are very unstable at room temperature and able to spontaneously or easily release a NO radical or NO anion (NO(-)), but releasing a NO radical is easier than releasing NO anion. These determined N-NO bond dissociation energies of G-MNBS and their radical anions have been successfully used in the mechanism analyses of NO transfer from G-MNBS to 3,6-dibromocarbazole and the reactions of NO with the substituted N-methyl-benzenesulfonamide nitranions (G-MBSN(-)) in acetonitrile solution.

Acetonitriles↗
PubMed2005

[Distribution of apoE polymorphism in Chinese Yunnan Dehong Dai ethnic group].

OBJECTIVE: To investigate the distribution of apolipoprotein E (apo E) polymorphism in Chinese Dehong Dai and Kunming Han ethnic groups. METHODS: After the process of extracting genomic DNA from 171 Chinese Dehong Dai and 71 Chinese Kunming Han subjects, the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was used to amplify the fourth exon of apoE, which contains site 112 and 158 in amino acid sequence, and the apoE polymorphism was detected. RESULTS: The genotyping frequencies of apolipoproteinE epsilon 2/2, epsilon 2/3, epsilon 2/4, epsilon3/3, epsilon3/4, epsilon4/4 in Dehong Dai were 0.006, 0.111, 0.006, 0.789, 0.088 and 0.000 respectively, while the genotyping frequencies of apoE epsilon2/2, epsilon2/3, epsilon2/4, epsilon3/3, epsilon3/4, epsilon4/4 in Kunming Han were 0.000, 0.169, 0.014, 0.718, 0.099, 0.000, respectively (P>0.05). The allelic frequencies of apoE epsilon2, epsilon3 and4 in Dehong Dai were 0.064, 0.889, 0.047 respectively, while the allelic frequencies of apoE epsilon2, epsilon3 and epsilon4 in Kunming Han were 0.092, 0.852, 0.056, respectively (P>0.05). CONCLUSION: The results revealed that either the frequency of genotype or that of allele of apoE gene polymorphism showed statistical difference between the ethnic populations. Compared with the data from other nationalities in China, the frequency of epsilon2 allele in Dehong Dai was significantly lower than that in Zhuang nationality (P<0.01); the frequency of epsilon3 allele in Dehong Dai was significantly higher than that in Chaoxian, Hui, Mongolian,Zhuang nationalities (P<0.05) and Uygur nationality (P<0.01); the frequency of epsilon4 allele in Dehong Dai was significantly lower than that in Olunchun nationality (P<0.05) and Uygur, Owenk nationalities (P<0.01). By comparison with the data from the populations of other races, the distribution of apoE gene polymorphism in Dehong Dai population is similar to that in Japanese population (P>0.05), but different from those in Singapore,European and American populations.

Adult↗
PubMed2005

[Screening of prothrombotic state-related genes from human hepatic cDNA library].

OBJECTIVE: To screen prothrombotic state-related cDNA sequences from human hepatic cDNA library. METHODS: The subtracted cDNA library for differentially expressed genes in rat liver of prothrombotic state (PTS) was constructed by suppression subtractive hybridization. Positive clones were identified by differential screening. The target DNA sequences of positive cDNA clones of differentially expressed genes from rat liver of PTS were amplified by PCR. The PCR products were used as probes to screen a human hepatic cDNA library. After the first, second and third screening, the transduction of a positive lambdaTripIEx lysate into E. coli strain BM25. 8 promoted the circularization of pTripIEx. The positive circularized plasmids were identified by double enzyme digestion. The cDNA fragments of the positive plasmids were sequenced and analyzed by bioinformatics (blastn). RESULTS: Four PTS-related cDNA sequences were identified from human hepatic cDNA library. For 3 of them, their products of expression were respectively fibrinogen, LFIRE1, and chromosome 10 open reading frame 104 mRNA. The fourth sequence had homology with carbamoyl-phosphate synthetase 1 gene. CONCLUSION: Four PTS-related cDNA sequences have been identified from human hepatic cDNA library.

Base Sequence↗
PubMed2005

[The effect of high density lipoprotein and oxidized high density lipoprotein on some secretive functions of endothelial cells].

OBJECTIVE: To investigate the effect of high density lipoprotein and oxidized high density lipoprotein on the synthesis of NO, the activity of NOS, and the secretion of tPA and PAI-1 by cultured human umbilical vein endothelial cells (HUVEC). METHODS: With the 0. 01 mol/L PBS and N-HDL of 50 mg/L as control, OX-HDL of 5 mg/L,10 mg/L, 50 mg/L were co-incubated with HUVEC for 24 h in vitro. The levels of NO, the activity of NOS, and the levels of tPA and PAI-1 in the medium were detected after the incubation. RESULTS: Compared with the 0.01 mol/L PBS control, the synthesis of NO(P < 0.05) and the activity of NOS (P < 0.01) were significantly increased in the N-HDL group, but the change of tPA and PAI-1 displayed no statistical significance (both P > 0.05). In the OX-HDL group, the synthesis of NO and the activity of NOS were significantly decreased in a dose-dependent way; the PAI-1 activity(P < 0.05) was increased, but the secretion of tPA (P > 0.05) was not affected. CONCLUSION: N-HDL significantly increased the synthesis of NO and the activity of NOS secreted by HUVEC, but it had no influence on the generation of tPA and PAI-1. On the contrary, OX-HDL significantly decreased the synthesis of NO and the activity of NOS; it significantly increased PAI-1 activity, but had no effect on the secretion of tPA.

Cells, Cultured↗
PubMed2003

Analysis of core histones by liquid chromatography-mass spectrometry and peptide mapping.

Histone acetylation and methylation are processes that are generally considered to play crucial roles in the chromatin-based regulatory mechanism. Characterization of the histones as well as their modification sites has become increasingly important. In this paper, the use of LC-MS and peptide mapping methods to analyze chicken core histones and identify the modification sites is reported. Microbore C(4) HPLC separated the core histones into H2A, H2B, H3 and H4 using HFBA as the ion-pairing agent. The four subclasses of histones and their putative acetylated or methylated isoforms were identified by LC-MS simultaneously. MALDI-TOF and tandem mass spectrometry provided peptide mapping of the modification sites of the histones through trypsin digestion of the HPLC eluents. This approach is straightforward and prospective for further application in the field of chromatin research.

Chromatography, High Pressure Liquid↗
PubMed2002

Identification of acetylation and methylation sites of histone H3 from chicken erythrocytes by high-accuracy matrix-assisted laser desorption ionization-time-of-flight, matrix-assisted laser desorption ionization-postsource decay, and nanoelectrospray ionization tandem mass spectrometry.

A new strategy has been employed for the identification of the covalent modification sites (mainly acetylation and methylation) of histone H3 from chicken erythrocytes using low enzyme/substrate ratios and short digestion times (trypsin used as the protease) with analysis by HPLC separation, matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF), matrix-assisted laser desorption ionization-postsource decay, and tandem mass spectrometric techniques. High-accuracy MALDI-TOF mass measurements with representative immonium ions (126 for acetylated lysine, 98 for monomethylated lysine, and 84 for di-, tri-, and unmethylated lysine) have been effectively used for differentiating methylated peptides from acetylated peptides. Our results demonstrate that lysines 4, 9, 14, 27, and 36 of the N-terminal of H3 are methylated, while lysines 14, 18, and 23 are acetylated. Surprisingly, a non-N-terminal residue, lysine 79, in the loop region hooking up to the bound DNA, was newly found to be methylated (un-, mono-, and dimethylated isoforms coexist). The reported mass spectrometric method has the advantages of speed, directness, sensitivity, and ease over protein sequencing and Western-blotting methods and holds the promise of an improved method for determining the status of histone modifications in the field of chromosome research.

Acetylation↗
PubMed2002

Death of preganglionic sympathetic neurons after surgical or immunologic lesion of peripheral processes.

Three months after systemic injection of antibody to acetylcholinesterase (AChE), there is a 60% decrease in the population of preganglionic sympathetic neurons expressing choline acetyltransferase (ChAT) in the intermediolateral (IML) nucleus of the rat spinal cord. In principle, the disappearance of identifiable cholinergic neurons might reflect either outright cell death or severe atrophy with downregulation of cholinergic markers. To distinguish between these possibilities, preganglionic neurons were labeled with the retrograde tracer dye, Fast Blue, 1 week before antibody injection or surgical transection of the cervical sympathetic trunk. Three months after either treatment, the thoracic IML contained 40-60% fewer Fast Blue-labeled neurons than in controls. Therefore, preganglionic sympathetic neurons do degenerate after antibody injection or axotomy. To clarify the role of axonal damage in this process, the effects of three different mechanical lesions were examined. A lumbar ganglionectomy designed to interrupt most sympathetic axons emanating from L2 IML caused 92% loss of ChAT-positive cells observed 10 weeks later at that site. In comparison, transection of the cervical sympathetic trunk, which spared some distally directed axonal branches from the thoracic IML, caused only a 46% loss of ChAT-positive neurons at T1. Still smaller effects were seen after the same nerve was crushed, a lesion that is less destructive. Thus, the ability of central sympathetic neurons to survive a peripheral lesion may be related to the degree of axonal damage and to the opportunity for axonal regrowth.

Acetylcholinesterase↗
PubMed2002

[Unilateral tonsillar enlargement and malignant tonsillar lymphoma].

OBJECTIVE: To study clinic characters of malignant lymphoma in patients with unilateral tonsillar enlargement for early discover and synthetic therapy clinic characters of malignant lymphoma patients with unilateral tonsillar enlargement for early discover and synthetic therapy. METHOD: 10 cases of non-Hodgkin's lymphoma (NHL) out of 100 unilateral tonsillar enlargement patients given tonsillectomy were treated with combined chemotherapy. 8 cases of 10 underwent local radiotherapy after operation. RESULT: 5 years survival rate was 60% in 10 patients with NHL. CONCLUSION: Progressing unilateral swollen tonsil found in a short time with suspicious appearance should be given tonsillectomy for histopathology; upper airway and systematic symptoms such as fever and rigors, night sweats; lymphatic enlargement in cervical, axillary, inguinal region; hepatosplenomegaly should be thought of main traits of malignant lymphoma, and hyposensitivity to medicine should be taken malignant lymphoma into account.

Adolescent↗
PubMedDate not supplied

An initial study on lip perception of electrotactile array stimulation.

We conducted an initial study on tactile sensory characteristics of the lips by applying electrotactile array stimulation on the center surfaces of the upper and lower lips. We performed experiments of threshold measurement and rating of two-line separation to evaluate the tactile sensitivity and spatial discriminating ability of the lips, respectively. Three stimulator arrays of different sizes presented electrotactile patterns on the lips of eight subjects (six male, two female) to measure the electrotactile performance in relation to stimulator size and spacing. Experimental results showed that the lips required very low intensities for effective electrotactile stimulation. As the stimulator diameter increased from 75 micrometers to 1.55 millimeters, the average stimulation intensity at the threshold level decreased from 12.5 to 6.3 V for the lower lip and from 13.3 to 7.1 V for the upper lip. Meanwhile, the two-line separation rating experiment showed that both upper and lower lips possessed high spatial discriminating ability. The average percentages of correct rating of two adjacent lines ranged from 80.5% to 88.2% on the two stimulator arrays with center-to-center spacing of at least 2.40 mm. In addition, sensitivity analysis indicated that the upper lip slightly outperformed the lower lip in spatial discrimination.

Adult↗